Railway car air conditioning system



March 22, '193B- H. L. SMITH. JR., ET Al. 2,111,905

RAILWAY CAR AR CONDLTIONING SYSTEM Filed Feb. 8, 1955 5 SheCS-Sheet l ATTORNEYS March 22, 1938. sMrrH. JR'.. ET AL 2,111,905

I RAILWAY CAR AIR CONDITIONING SYSTEM Filed Feb. 8, 1935 Ssheets-sheet 2 ATTORNEYS d1 22, 1938 H. L. SMITH, JR.. ET A1. y

` RAILWAY CAR AIR CONDITIONING SYSTEM 5 Sheets-Sheet 3 Filed Feb. 8, 1935 Y mmv. www mx f lN ma cENToR N mdff fm/@ WAM/3M ATTORNEYS March 22,A 1938.'- SMITH, JR., E'T AL i 2,111,905

RAILWAY GAR AIRCONDITIONING SYSTEM 'Filed Feb. 8,. 1935 5 sheets-sheet 4 M, @AA/al i ATTORNEYS H. L. SMITH, JR., ET AL.

RAILWAY CAR AIR CoNDlToNING SYSTEM March 22, 1938.

Filed Feb. 8, 1935 y5 Sheets-Sheetv Ji J/ Z7 6 BY 77M/ m.

ATTORNEYS Patented Maf. l2:2, 193sv UNiTED STATES PAT-ENT oFl-lcE u RAILWAY oAa Ala CONDITIONING SYSTEM Horace L. Smith, Jr., and Lucian N. Jones,

Richmond, Va., assignors to Thermal Engineering Corporation, Richmond, Va., la corporation of Virginia Application February s, 1935, serial No. 5,532 1o claims. (ci. ca -152) This invention relates to air conditioning and more particularly concerns an improved air conditioning system -for use on railway passenger cars.

5 It is highly desirable that passenger carrying u railway cars, such as coaches, sleeping cars, diners and the like, be provided with air cooling, heating and conditioning equipment, in onder to maintain comfortable conditions regardless of wide variations in the outdoor-temperature and humid- .ity encountered in railway car operation.l In a single trip, a railway car may travel from an extremely cold, dry climate to regions where hightemperature and high relative humidity prevail and even reasonably comfortable atmospheric conditions cannot be maintained by ventilation alone because of the dust and smoke incident to railway-travel. The problem of conditioning the air in a railway car 4is primarily one of cooling and o dehumidifying, since particularly on steam operated trains, the heating of the cars is a relatively simple matter.

It has been proposed to equip railway cars with air cooling and dehumidifying systemsV embodying 5 apparatus which is operated in whole or in part by electricity. Systems of this type are unsatisfactory because of their highinitial cost and the high operating cost resulting from their low efiiciency. Thus, when such systems are installed on a railway car, it is neceary to replace the usual car lighting generator and battery with electrical generating and accumulating equipment of greatly increased capacity, and this replacement materially increases the initial cost of 5 the installation' The energy for operating electrically driven systems is delivered from the locomotive through the draw bars, the axle driven generator, the storage battery andthe electric motors to the refrigerating apparatus, and cono sequently, the overall efciency of the system is low andthe operating cost correspondingly high. Another vserious disadvantage of electrically driven air cooling apparatus forI railway cars arises from the,fact that-the servicing personnel Y 45 and equipment available on steam roads are largely unsuited to handle the repair and maintenance of extensive electrical apparatus of this type. Railway servicing departments are necessarily familiar with repairs to apparatus employing'steam 50 land compressed air, but have little or no occasion to handle the servicing of electrical apparatus of large capacity. 1 The space available for vthe installation of cooling and air conditioning equipment. on a pasu senger carrying railway car is very hunted, and

in general, the cooling equipment must be disposed beneath the oor frame of the car. The necessary right-of-way clearances and the presence of brake-operating and car lighting equipment beneath the car leaves very little free space 5 for the cooling equipment. Due to these space limitations, many previously known railway car air conditioning systems employ a plurality of separate `under car units to make up the cooling apparatus, and this arrangement adds to the in- 10 stallationV cost and complicates the servicing problems. i l

With the above and other considerations in mind, it is proposed in accordance with thepres- 1 ent invention to provide an improved, compact l5 and highly eiiicientrailway car air conditioning system embodying refrigerating or cooling apparatus directly operated by steam alone. The system of the invention includes refrigerating or cooling equipment comprising a single unitary structure embodying structural and operating improvements which reduce its size to such an extent that it may be readily mounted in the limited free space available beneath the lfloor frame of a standard railway car. The invention further contemplates the provision of railway car cooling or refrigerating apparatus which is so constructed and arranged that the elements or parts thereof which require servicing or repair are readilyaccessible and may be removed without 30,

disturbing the remainder of the apparatus.

A further object of the invention is the provision of improved and eiective means for pre cooling passenger cars when they are stationary 'and unattached to a locomotive. 35

"Various other speciiic objects and advantages of the invention will become apparent as the description thereof progresses.

In general, the above and other objects of the' invention are carried out by providing a railway 40 car air conditioning system embodying improved cooling or refrigerating apparatus in which a partial vacuum is maintained in a chill tank or evaporator by means of a steam jet operated vacnum booster. The water or other liquid cooled in the chill tank is circulated in heat exchanging relation with the air in the railway car and in this manner, the car airis cooled and dehumidified-as req red. The improved liquid cooling or refrigerating apparatus is entirely operated directly by steam, and to this end, preferably employs a single condenser, cooled by air circulation and water sprays. The apparatus for circulating the chilled liquid from the tank or evaporator and for circulating the'c'ondenser cooling wat r and air as well 55 as for extracting condensate from the condenser is preferably operated by a steam turbine and the exhaust steam from this turbine as well as from.

the Asteam jet vacuum booster is condensed in the condenser.

The vacuum cooling apparatus of the invention includes an improved chill tank construction in which a steam jet vacuum creating means or booster is disposed directly within the chill tank proper, thereby simplifying the construction and increasing the eiciency of the vacuum booster. I'he improved chill tank is provided with means for greatly increasing the surface area of lthe liquid therein whereby the evaporative capacity of the chill tank is greatly increased.

The devices comprising the refrigerating or cooling apparatus of our improved system are preferably disposed in an extremely compact arrangement and are housed and supported to form a single unitary structure of a size and shape suitable for mounting beneath a standard railway car. lThe apparatus is preferably so constructed and arranged that certain devices, such as the steam turbine and the liquid pumps operated thereby, which require periodic servicing or repair. may be readily removed from the unitary structure without disturbing the remainder of the apparatus.

Our improved means for pre-cooling railway cars equipped with our improved air conditioning systems preferably comprises a unit for supplying chilled water or other liquid from a portable source independently of the car-carried refrigerating apparatus to the air cooling coil or heat exchanging means of the car. By the use of this auxiliary equipment, railway cars may be pre-cooled while standing in passenger stations or railway yards without the necessity of attaching such cars to a locomotive or supplying steam from some other source to operate the carcarrying refrigerating equipment.

The invention will be best understood by reference to the accompanying drawings in which an embodiment thereof is illustrated. In the drawings;

Figure 1 is an elevation, partly in section, of aportion of a railway car equipped with air conditioning apparatus embodying the invention, together with pre-cooling equipment for the car;

Figure 2 is an elevation, partly in section, of

Y the refrigerating unit of a system embodying the invention;

Figure 3 is a, plan view of the unit of Figure 2 with the upper wall of the unit housing broken away to show the interior construction;

Figure 4 is an enlarged plan view of the lower portion of the condenser compartment of the unit of Figure 2;

Figures 5 and 6 are respectively sectional views taken along the lines 5-5 and 6-5 of Figure 2 and viewed in the direction of the arrows;

Figure 7 is an enlarged transverse section of the chill tank of the refrigerating equipment; and

Figure 8 is a longitudinal section of the chill tank taken along the line 8-8 of Figure 7.

Referring to the drawings, our improved railway car air conditioning system has been shown as applied to a railway passenger car of conventional construction which has been diagrammatically illustrated at P in Figure l. The system is of the type in which chilled water or other liquid is circulated in heat exchanging relation with air supplied tothe car. Theparticular form of heat exchange and air propelling means used forms no part of the present invention, and various forms of apparatus may be employed for this purpose. i shown in Figure 1, fresh air from outside of the car is drawn by a fan 3 through one or more intake openings 2 into a chamber 4 located above .the ceiling of the car vestibule I and is propelled by the fan through a duct 5 to suitably placed ceiling outlets 5 in the car. A cooling coil 6 is located in the chamber 4 in heat eX- changing relation with the air drawn there through, and this coil is at times supplied with chilled water or other liquid from a refrigerating unit hereinafter described. A heating coil 8, 'supplied at times with steam from the train steam line, is also located in the chamber 4. The fan 3 may be operated by an electric motor 9,

In the embodiment as shown. The fan 3 and motor 9 may be of relatively small capacity and may replace the usual electric fans customarily installed in railway passenger cars. Air may be discharged from the car through the doors, windows or other air pervious openings thereof, or special air outlet ducts may be provided, ify desired.

In accordance with the present invention, chilled water or other liquid for use in cooling the air delivered to the car is supplied by refrigerating apparatus comprising a unitary struc- I ture carried beneath the car and designated U in Figure l. Steam from the train line is supplied to this unit through a pipe I0 and steam for heating the car heating coil 8 is returned from control devices in the unit U through the pipe I8. Chilled water is delivered from the unit U to the car cooling coil 6 through the pipe II and returned through the pipe I2. Valve controlled branch connections I3 and I4 are provided on the water pipes II and I2 respectively for a purpose hereinafter described. The water pipes II and I2 are preferably enclosed in an insulating duct illustrated at I5 and a steam pipe I6 is also enclosed in this duct and at times supplied with steam to prevent freezing of the water in the pipes II and I2.

The refrigerating apparatus of the unit U is enclosed in an elongated housing H suitably secured to the under surface of the car floor frame I1 adjacent one side thereof. One end of the housing H comprises a condenser compartment C which is separated from the remainder of the housing by the transverse substantially centralports 23. A pumping unit including a steam turbine T is provided on the bottom wall of the housing H between the condenser compartment C and the blower 20 and substantially beneath the chill tank 22.

'I'he condenserv of the refrigerating apparatus is cooled by air circulationv and a water spray. The condenser proper comprises a pair of spaced headers 24 and 25 connected by the elongated finned tubes 26. The condenser is so mounted that the tubes 26 lie at an angle to the horizontal, the inlet header 24 being secured near the upper wall 21 of the housing H at the outer end of the condenser compartment C by a bracket 28, and the outlet header 25 being suitably supported adjacent the opposite end of the condenser compartment at a considerably lower level than the inlet header 24. As shown in Figures I3 and 5,- the inlet header 24 has a lateral extension .29 passing through the side wall of the condenser compartment C and into a compartment 3| extending along one side of the condenser compartment, arid an exhaust pipe 32 is connected to this header extension 29, as shown.

Suitable openings are provided for permitting the passage of cooling air through the condenser compartment C in such a direction that this air passes through the tube bundle of the condenser proper over the surfaces of the finned tubes 26. Thus, the bottom wall of the condenser compartment C is substantially open and comprises a series of air permeable filters 33, removably supported on transverse supporting beams 34, as shown in Figure 2. The filters 33 maybe of any suitable construction, and as shownin Figure 5, may com'prise a mass 35 of interengaging strands compressed between parallel screens or perforated plates 36. The filters 33 are preferably r'emovable for replacement or cleaning through the lower side wall 31 of the condenser compartment C, which wall isl hinged at 38 as shown in Figure -5 and may be swung upward to the position shown in dotted lines, whereupon the filters 33 may be disconnected from thelongitudinal supporting angles 39 and v4|'.I and removed laterally from the unit.4 A latch mechanism 4| is provided for securing the hinged wall 31 in its open and closed positions.`

- An air inlet opening is also provided in the end wall 42 of the condenser compartment C and an air filter 43 is removably secured over this opening by suitable brackets 44 and clamping bolts 45. A set of louvers or air deflectors 46 is secured withinthe end inlet opening to deflect the entering air downward beneath the condenser tubes 26. A bracing rod 58 passes through the louvers 46 adjacent their centers, as shown in Figure 5.

The louvers 46 are preferably removable to give access to the interior of the condenser compartment C.

The air outlet of the condenser compartment C comprises an opening through the vertical transverse partition I9. As shown in Figures 2, 3, 4 and 6, Athis opening is filled with a set of eliminator plates 41 carried in a frame 48 having a marginal flange 49 along the lower outer edge, as best shown in Figure 4. The eliminator plates 41 are of known construction, comprising angularly disposed parallel plates having inwardly opening pockets 58 thereon for collecting and carrying off any spray water that may be carried by the air passing through the partition opening.

Two sets of spray water pipes are provided in the condenser( compartment C, one set lying above and the other below the condenser tubes 26. The upper set comprises a series of transverse pipes 5| connected through the vertical pipes 56 to the ,manifold pipe 52 in the side compartment 3|,

and these transverse pipes 5I extend through the side wall 3|) and across the condenser compartment C adjacent the top wall 21 thereof, their ends being supported 'by suitable lugs 53 on the inner housing wall 54. A plurality of spray heads 55 are provided on eachof the pipes 5| within the compartment C and are disposed to direct a spray .of water from the pipes 5| downwardly onto the condenser tubes 26. An angular extension 51 of the manifold pipe 52 passes through the side wall 30 and extends across the outer end of the condenser compartment C beneath th'e header 24. v

' water from the heads The lower set of spray water pipes 59 extend longitudinally along the condenser compartment C from the pipe 51, and their inner ends are car-- ried by brackets 60 depending from the lower or outlet header 25 of the condenser. Two sets of spray heads 6| and 62 are provided on each of thepipes 59, the set 6| directing spray water upwardly against the condenser tubes 26 and the set 62 directing spray water downwardly into the air entering 4through the filters 33.

Meansare provided for collecting and removing the spray water from the condenser compartment C. This means preferably takes the form of a plurality of spaced parallel concave troughs 63 extending transversely across the lower portion of the compartment and inclined toward the inner wall 54, as shown in Figure 5. 'Ihe spaces between the concave troughs 63 are bridged by the convex defiectors 64 which are spaced some distanceabove and disposed in overlapping relation'tothetroughs 63, as shown in Figure 2. The outer ends of the troughs 63 are carried by a longitudinal angle beam 65 and their inner ends extend through openings in the inner wall 54 of the condenserl compartment and into a water sump or collecting tank 66 secured outside of the inner wall 54 adjacent the lower edge thereof. vThe convex deflectors are suitably secured between the side walls ofthe compartment C and a marginal gutter 61 is disposed above these deflectors and extends aroundl the four walls of the compartment, as shown in Figure 4.v The por- 'tions of the gutter 61 extending across the ends of thecompartment C protrude outwardly over the edges of the concave .water troughs 63, as shown in Figure 2. An `angle member 68 is disposed between the inner lower edge of the eliminator frame 48 and the upper edge of the gutter 61, so that water entrained by the eliminator plates 41 drains back over this angle member and denser tubes 26, as shown. This loop insures the condensation of any vapor leaving the condenser. The outlet pipe 69 extends through the central partition I9 just below the air. outlet therethrough, as shown in Figure 2.

The blower 20 is provided with inlet openings 10 at its sides, and when this blower is in operation, air is drawn into the condenser compartment C through the filters 33 and 43, passes u'pwardly through the bundle of condenser tubes 26,

and out of the condenser compartment -through the eliminator plates 41, nally entering the blower inlets 10 and out of the housing throughl the blower outlet 2|.` The entering air is cooled by the evaporation therein of water from the downwardly directed spray heads 62 and spray 55 and 6| facilitates the rapid transfer of heat from the condenser tubes 26 to the air passing over these tubes.

The refrigerating equipment is located in the compartment D to the right .of the partition I9, as viewed in Figures 2 and 3. This compartment D is preferably thermally insulated by suitable means, such as the sheets ||8 of insulating may terial carried by the walls thereof, as shown. The chill tank or evaporator 22 and steam jet booster B are of improved design. The chill tank 22 is preferably cylindrical and disposed transversely of the housing H. A water inlet pipe 1| is connected through the end head 12 of the chill tank and this inlet pipe is connected to the return pipe I2 from the c'ar cooling coil 6. As shown in Figures '1 and 8, the inlet pipe 1| extends substantially across the interior of the tank 22 at the top thereof, and is provided with a plurality of oppositely disposed substantially horizontal outlet openings 14. 15 having perforations 16 therethrough is suitably supported below the pipe 1| and serves to distribute the incoming water in fine streams or drops about the interior of the tank.

In accordance with the invention, the steam jet vacuum booster B is located directly Within the chill tank 22. As shown in Figures 2, 3 and 8, this booster comprises a cylindrical casing 11 passing horizontally directly throughthe chill tank 22 and sealed in aligned opposite openings in the cylindrical wall thereof. A steam nozzle 18 of proper design is carried by the head 19 of the casing 11 and is supplied with steam from a pipe 88. A tapered throat 8| is secured within the casing 11 in axial alignment with and spaced from the nozzle 18 and a plurality of openings 82 are formed in the casing 11 adjacent the nozzle outlet and the throat inlet to admit vapor from the chill tank 22 to the throat 8|. The location of the steam jet booster B directly within the chill tank 22 not only provides an extremely compact construction, but also improves the efficiency of the apparatus Thus, with this arrangement, vaporgfrom the evaporating water in the tank 22 ows directly to the entraining steam jet and into the throat 8|' from opposite sides of the'jet, and frictional losses due to unsymmetrical vapor flow to and through the jet are largely eliminated.

The Venturi throat 8| is connected to a complementary throat section 83 passing through the partition I9 and connected at its end with the exhaust pipe 32 in the compartment 3|. It will be noted that the throat comprising the sections 8| and 83, as well as the exhaust pipe connected thereto, presents a straight unobstructed passage of considerable length aligned with the steam jet of the booster B. This arrangement permits the efficient operation of the boosterA since undue frictional retardation of the exhaust fluid prior to complete expansion is avoided and a high uid velocity through the booster throat is obtained. The straight throat and exhaust passage are employed Without increasing the, overall length of the refrigerating unit since the. outer end of the exhaust pipe 32 is connected to the outer and upper condenser header 24 and the condenser tubes 26 extend back substantially longitudinally of the unit housing H and occupy.

the same longitudinal space as the booster throat and the exhaust pipe.l

We prefer to employ novel means for increaslng the evaporating capacity of the chill tank. This means takes the form of a plurality of small helical coils of wire' 84 loosely disposed in the chill tank beneath the water distributing tray 15. A coarse transverse screen 15' extends across the chill tank adjacent the steam jet booster B to prevent the coils'84 from entering the booster throat. Water from the tray 15 spreads in a thin lm on the surfaces of the coils 84 and thus presents a very large surface area from which evaporation takes place at a very rapid rate. Various forms of coils may be used, and in gen- A distributing tray eral, any type of coil in which the successive turns are spaced apart may be employed. Since the surface area of the liquid distributed on the coils 84 is considerably greater than the largest level surface area obtainable in the tank 22, it is preferred to keep the liquid level at a low point within the tank as indicated at |55.

Any suitable means may be employed for maintaining the liquid level in the chill tank 22 constant.- As shown in Figure '1, a float operated valve' may be provided in a compartment |56 connected to the tank 22 adjacent the bottom thereof, this valve being arranged to control the admission of liquid to the tank. The simple form of float valve disclosed includes a float |51 bearing directly on a valve plug |58, the valve plug cooperating with a seat |59. Suitable guide means |68 guide the valve plug |58 to the seat |59. The valve seat |59 is connected to the water tank or sump 66 by a pipe |6l. When the water level within the chill tank 22 and the connected compartment |56 drops below the point desired, the float |51 falls and permits the plug |58 to disengage the seat |59, whereby .water flows from the sump 86 into the chill tank 22 because of the sub-atmospheric pressure` maintained inthe chill tank by the steam jet booster B. When the water level has risen to the required peint, the admission of further water is cut off by the rising of the float |51 and the closing of the valve |58.

The pumping \equipment of the refrigerating apparatus comprises a unitary structure carried by a base plate 85 mounted on the bottom wall of the compartment D. As shown in Figures 2, 3 and 6, this equipement comprises a vacuum suction pump 81, a chilled water circulating pump 88 and a spray water pump 89, all driven by a centrally located steam turbine T. The suction pump 81 operates at a high speed and is directly connected to the turbine shaft 90, as shown, and the casing of the pump 81 is preferably connected to the.turbine casing and the base 85 by suitable brackets or webs 9| and 92. The pumps 88 and 89 operate at a lower speed than the suction pump 81 and are driven by the turbine T at a suitably reduced speed through a spiral or worm gearing connection located in the housing 93, this housing carrying the common drive shaft 94 of the pumps 88 and 89 at right angles to the turbine shaft 98. The casings of the pumps 88 and 89 are connected to the gear housing 93 by the Webs 95, and similar webs 98 connect the gear housing 93 to the casing of the turbine T whereby a rigid unitary structure is provided. A pulley 91 is xed to the end of the turbine shaft 98 beyond the gear housing 93 and a belt 98 effects a driving connection between this pulley and a driving pulley 99on the shaft of the blower 20.

The vacuum suction pump 81 has an intake pipe |88 connected through the control valve |8| and the pipe |82 to the outlet pipe 69 of the condenser, while the outlet pipe |83 of the pump 81 extends through the partition I9 and discharges over the angle member 68 and gutter 61 through the transverse trough 63 and into the water sump 66, as best shown in Figures 2 and 3. The pump 88 is connected to withdraw Water from the bottom of the chill tank 22 through the pipe |84 and to discharge this water through the -pipes |85 and to the car cooling coil 6. The spray water pump 89 is connected to draw water from the sump 66 through the pipe |88 and to deliver water through the pipe |81 to the spray manifold pipe 52.

A restricted pipe |08 delivers 'Water at a limited rate from the casing `of the spray water pump 89 to the casing of the vacuum suction pump 81,

thus maintainingthe required amount. of sealing 'water inthe suction pump casing.' A similar restricted pipe |09 connects the inlet ports of the spray water pump 89 and the `vacuum suction pump 81 whereby Water is drawn from the sump 66 by the suction of the pump 81 to -prime the the pipe I8 to the car .heating coil. 8. Exhaust steam from the turbine T passes through the pipe |26 extending through the partition |9 and flows l'to the exhaust pipe 32 and thence to the upper header 24 of the condenser.

In accordance with the invention, thepumping equipment includingthe turbine T is conveniently removable from the housing H as a unit. To this end, the base 85 of the pumping equipment is supported onl a removable wall section which `comprises a pair of transverse channel beams ||0, removably bolted at their ends to the longitudinal housing beams and-H2 andwcarrying the housingl wall plate H3, as

shown in Figures 2 and 6. A pair of removable access plates 4 and ||5 are respectively disposedl on either side of the plate ||3 4being secured to the adjacent sections of the bottom wall of the housing by suitable transverse angle bars |21 and bolts |28, as clearly shown in Figure v2.

' When it is desired to remove the pumping equipment for inspection, replacement or repair, the plates I |4 and ||5 are removed and the openings thus provided give access to the connections be tween the pumping equipment and the other apparatus. The belt 98 is removed from the pulley 99, the -iianged couplings |29 and |30 in the intake and outlet pipes |04 and |05 of the chilled water circulating pump 88 are disconnected and the ilanged couplings |3| and |32 in the intake and outlet pipes |06 and |01 of the spray water pump 89 are disconnected. The steam supply Vpipe |22 of theturbine T is disconnected at the union |33 and the turbine exhaust pipe |26 is opened at the anged coupling |34. 'I'he condenser outlet pipe 69 is disconnected fromV the suction pump 81 at the union |35 and the outlet pipe |03 of this pump is opened at the union |36. The pumping equipment includingthe tur' bine T and the pumps 81,88 and 89 is thus entirely disconnected from the other apparatus in the housing, and may be removed as a unit by removing the bolts |31 at the ends of the channel beams and lowering these beams, thereby withdrawing the pumping equipment from the housing H.

The operation of the 'refrigerating apparatus in cooling the railway car will be readily apparent to those skilledin the art. When conditions require that the car air be cooled and dehumidi4 'vacuum booster steamv supply valve U9, As the turbine T starts up, the suction pump 81 creates a vacuum in the intake ofthe spray water pump 89 and so draws water from the'sump 66 through the pipe |06 to prime the pump 89. .The pump- 89`then forces water drawn from the sump 66 through the pipes 52, 56, 51, 5| and 59 tb the spray heads 55, 6| and 62 in the condensercompartment, a large portion of this spray'water being returned to the sump 66 by the troughs 63. The blower 20 draws cooling air through the condensercompartment C from the lters 33 and 43. The steam jet booster B evacuates the chill tank 22 and causes the evaporation and consequent cooling of the water therein, and this Y chilled water is circulated through the car cooling coil 6 bythe pump 88. The water lost from the circulatory system including the car cooling coil 6 andl chill tank 22 by evaporation in the chill tank is made up by water drawn up from the sump 66 through the pipe 6| under the control of the float |51 and the valve plug |58 operated thereby. The exhaust steam from the booster v13 and the turbine T is condensed in the condenser tubes 26 and the vacuum suction pump 81 purges the condenser of condensate and air and delivers the condensate to the sump 66.

The return of condensate-from the condenser 4to the water sump 66 assists in making up for water lost from the system by evaporation in the condenser compartment. However, some additional make up water is. required and awater make up tankl38 isv accordingly provided, connected as shown in Figure 1 beneath the car oor frame `|8 'adjacent one end of the refrigerating apparatusunit U.l The makeup water tank v|88 may be of any suitable constructionv and4 is preferably arranged to maintainl a constant water level in the sump `66. To this end, the tank |38 vis connected to the -sump 66'by a pipe '|39 entering the sump below the water level therein as shown in Figures 1 and 5, and a vent pipe |40 extends from apoint adjacent the upper end of the tank |38 to a point just below the water level in the sump 66 and above the water feed pipe |39. With this arrangement, when the water level in the sump 66 `falls below the end of y the vent pipe |40, air enters'this pipe. and relieves the vacuum in the tank |38, thus permitting Vance with our invention, this may be conveniently accomplished without the necessity for connecting a locomotive or other source of steam to the cars. To this end, we provide means for circulating chilled water through the coolingcoil 6' independently of the refrigerating unit U. As

shown in Figure 1, the chilled water supply uand return pipes ll'and I2 are respectively provided with branchvducts I3 and |84 and threefway valves |4| and |42 of conventional construction are provided at the junctures of these branch ducts with the chilled water circulating pipes.

The three-way valves |4| and |42 actin a known manner to either cut othe branch ducts I3 and 4 and open the pipes and I2, or to connect the pipes to the-branch ducts and cut oir the pipes from the car-carriedrefrigerating unit U.

Chilled water for circulation through the pipes and I2 may be supplied from a truck |43 carrying a closed heat insulated ice bunker |44 with a spray pipe |45 at the top thereof and an Athence to the chilled water feed pipe II.

outlet pipe I46 at the bottom thereof as shown. A water circulating pump |41 driven by an electric motor I 48 is connected to the outlet pipe |46, and energy for operating this pump may be supplied from an electrical outlet in the car yards or station where the railway car is standing. The inlet; spray pipe I45 is connected by a flexible hose |49 to the branch duct I4 and ,thence to the chilled water return pipe I2, and

the outlet of the pump |41 is connected by a flexible hose |50 to the branch duct I3 and When the pump |41 is operated, chilled water is drawn from the ice bunker |44 and delivered through the hose |50, the branch duct I3 and the pipe II to the car cooling coil-Ii, returning through the pipe I2, the branch duct I4, the hose I 48 and the spray pipe I 45 and running over the ice cakes I5I in the bunker |44. The air blower 3 in the car is operated to draw air over the cooling coil 6 and into Ithe car. This operation is continued until the car temperature is reduced to the required point and the car is ready to be connected to a locomotive.

We claim:

1. Refrigerating apparatus for a railway car air conditioning system comprising a horizontal 1y extending elongated housing, a chill tank extending transversely of said housing and spaced from one end thereof, a steam jet vacuum boosr connected to evacuate said chill tank and extending longitudinally of said housing adjacent the top Wall thereof, a throat member and an exhaust duct connected to and aligned with said booster, said exhaust duct terminating near one end of said housing adjacent the top wall thereof, a condenser comprisinga plurality of elongated tubes extending longitudinally of said housing downwardly at an angle to the horizontal from a point adjacent the end of said exhaust duct toward said chill tank, means connecting the nd of said exhaust duct to the upper ends of said condenser tubes, said housing having air inlet openings beneath said condenser tubes and means for expelling air from said housing adjacent the end thereof remote from said condenser whereby air is drawn through said inlet openings and upwardly over said condenser tubes.

2. Refrigerating apparatus for a railway ,car air conditioning system comprising a horizontally extending elongated housing, a chill tank extending transversely of said housing and spaced from one end thereof, a steam jet vacuum booster connected to evacuate said chill tank, and extending horizontally adjacent the top of said housing near one side thereof, an exhaust duct `connected to and aligned with said vacuum booster and extending therefrom along one side of said housing and terminating at a point ad.

extending diagonally downward toward the other end of said housing, said housing having air inlet the type in which a chilled liquid is circulated in heat exchanging relatiolf with air delivered to the car, car-carried refrigerating apparatus for chilling the liquid so circulated comprising a horizontally extending elongated housing, a condenser in said housing adjacent one end thereof, said housing having an air. inlet opening therein adjacent said condenser, means in said housing for spraying water on said condenser, an air blower in 'said housing adjacent the other end thereof connected to discharge air from said housing whereby air is drawn over said condenser from said inlet opening, a chill tank in said housing between said condenser and said blower, steam jet means connected to evacuate said chill tank, pumping means` for circulating liquid through said chill tank, supplying water to said condenser spraying means and withdrawing fluid from said condenser, a steam turbine connected to operate said pumping means and said air blower, said turbine and said pumping means being disposed substantially beneath said chill tank and between said condenser and said blower, and means for conducting exhaust steam from said jet evacuating means and from said turbine to 4 said condenser.

4. In a railway car air conditioning system of the type in which a chilled liquid is circulated in heat lexchanging relation with air delivered to the car, car-carried refrigerating apparatus for chilling the liquid so circulated comprising a horizontally extending elongated housing, a condenser in said housing adjacent one end thereof, said housing having an air inlet opening therein adjacent said condenser, means in said housing for spraying water on said condenser, means disposed adjacent the other end of said housing for circulating air from said inlet opening over said condenser, a chill tank and a "steam jet evacua'tor therefor disposed adjacent the top of said housing between said condenser and said air circulating means, pumping means for supplying water to said condenser spraying means. means for circulating liquid through said chill tank, a steam turbine connected to operate said pumping and circulating means, said turbine and said pumping and circulating means being mounted below said chill tank adjacent the bottom of said housing between said condenser and said air circulating means and means for conducting exhaust steam from said turbine and said steam jet evacuator to said condenser.

5. Refrigerating apparatus for a railway car air conditioning system comprising an elongated housing, a chill tank in said housing spaced yfrom one end thereof, a steam jet vacuum booster connected to evacuate said chill tank and disposed longitudinally of said housing, a substantially straight expansion throat rand exhaust duct extending longitudinally of said housing and aligned with said booster, an elongated condenser connected to said exhaust duct and disposed substantially longitudinally of said housing beside said exhaust duct and expansion throat, a steam turbine arranged to discharge to said exhaust duct and means driven by said turbine for circulating water through said chill tank, circulating air and water in heat exchanging relation with said condenser and withdrawing fluid from said condenser.

6. Refrigerating apparatus for a railway car air conditioning system comprising a chill tank, a steam jet vacuum booster connected to evacuate said chill tank, a condenser connected to receive exhaust steam from said booster. means for circulating water in heat exchanging relation with said condenser, means for circulating cooling air over said condenser, a vacuum pump for withdrawing fluid from said condenser, means for circulating Water through said chill tank and a steam turbine exhausting into said condenser and connected to drive said condenser Water circulating means, said cooling air circulating means, said vacuum pump and said chill tank water circulating means.

7. In a railway car air conditioning system, a unitary housing and refrigerating apparatus in said housing comprising a chill tank, steam jet evacuating means connected to evacuate said chill tank, a condenser connected to receive the exhaust from said steam jet evacuating means, means for spraying water over said condenser, a suction pump connected to said condenser, a pump connected to circulate water through said chill tank, a pump connected to deliver Water to said condenser spraying means, and a steam turbine connected to drive all of said pumps and having an exhaust duct connected to said 'condenser.

8. In a railway car air conditioning system, a car-carried housing and refrigerating apparatus in said housing comprising a chill tank and steam jet evacuating means therefor, a condenser con-.

`means on said removable wall section, and at least one removable access plate in said housing adjacent said removable Wall section disposed to combination with a railway car, a housing mounted beneath said car and having a removable wall section in the bottom wall thereof, refrigerating apparatus in said housing comprising a chill tank and steam jet evacuating means therefor, a coni denser connected to receive exhaust vapor from said evacuating means, means' for spraying water on said condenser, a chilled Water circulating pump connected to said chill tank, a suction pump connected to said condenser, a spray W'ater pump connected to said condenser water spraying means, a steam turbine arranged to discharge to said condenser, driving connections between all of said pumps and said turbine, means for mounting all 'of said pumps, said turbine and said driving connections on said removable wall section, and at least one removable access plate forming a part of the bottom wall of said housing adjacent said removable wall section for giving access to the connections to said pumps and said turbine. 1

10. In refrigerating apparatus for railway car air conditioning systems, in combination, a chill tank and means for evacuating said chill tank comprising an elongated cylindrical duct sealed in opposite openings in said chill tank, a steam nozzle adjacent one end of said duct terminating at a point within said chill tank, and a tapered throat in said duct aligned with said nozzle and spaced from the end thereof, said duct having a 

